Cat 246 - Strange Sound w/Drive Issues

Out of nowhere my machine starts to make a noise that sounds kinda like tires squeaking on a polished concrete floor. It even sounds like it's coming from the wheel/tires - but that's clearly not what's going on.

Whatever it is also affects the ability to drive it - it feels like something is binding up keeping the wheel from wanting to rotate. This happened last week and I shut it down. When I came back out to my property to load my machine on to my trailer a yesterday, it had resolved on its own and it ran just fine. I ended up using it to move dirt for about three hours without any issues. Well today I go out to use it and after about an hour and a half, the problem came back.

Here's a short video:

Any thoughts on the cause?

Sounds like an axle bearing locking up

Vetech63 said:

Sounds like an axle bearing locking up

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Is there aanything I can do to confirm this? I'm assuming each wheel has its own set of bearings?

01Time said:

Is there aanything I can do to confirm this? I'm assuming each wheel has its own set of bearings?

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Yes, each axle will have an inner and outer bearing . You can get the machine tires off the ground and check for a slight bit of roll on each wheel, each should move slightly forward and backward by hand. By the sound of yours I would bet one won't move at all. That one is more than likely the failing axle.

Definitely sounds like a seizing wheel bearing.

Might even be able see with a thermal camera, IR temp gun or feel the heat from that particular wheel end. Or, a length of hose/stethoscope to narrow it down. ( don’t get ran over).

I checked the axles and they all seemed okay. But, the issue intermittently persisted so I took it into Caterpillar. Being an intermittent problem it took a while for the symptoms to appear. But they did, and they were able to determine that the sound is coming from the left drive motor - not a cheap repair. Brand new, a new drive motor is $4000 (USD), or can get a Cat Reman for $2600, or a third-party rebuilt for around $2000. And Caterpillar is saying labor would be $500-600.

How difficult is it to rebuild myself? Is it just a matter of replacing bearings and seals? Are there rebuild kits available? If not, where would be a good place to get a list of parts needed?

01Time said:

How difficult is it to rebuild myself? Is it just a matter of replacing bearings and seals? Are there rebuild kits available? If not, where would be a good place to get a list of parts needed?

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To attempt to answer those questions would need the machine Serial Number.

Nige said:

To attempt to answer those questions would need the machine Serial Number.

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Ah, of course! 5SZ07867

OK, here we go. Hopefully others may offer their experiences.

How difficult is it to rebuild myself? - There are no instructions on the Cat system regarding disassembly & assembly of that motor so you'd be flying blind. IIRC I heard somewhere (I may be wrong) that these motors are made by Rexroth . If that is the case then there might be some information available outside the Cat system.
Is it just a matter of replacing bearings and seals? Depending on what is failing/has failed inside the motor it might be a bit more complicated that that.
Are there rebuild kits available? No, apart from a kit of seals and gaskets. See attachment.
If not, where would be a good place to get a list of parts needed? The attachment is what the Parts Manual shows as being available for that motor. Anything that is not listed separately is not available without buying a complete motor. To ensure the Parts List is the correct one for your motor please check that yours has a 220-8162 Part Number tag on it.

Nige said:

OK, here we go. Hopefully others may offer their experiences.

How difficult is it to rebuild myself? - There are no instructions on the Cat system regarding disassembly & assembly of that motor so you'd be flying blind. IIRC I heard somewhere (I may be wrong) that these motors are made by Rexroth . If that is the case then there might be some information available outside the Cat system.
Is it just a matter of replacing bearings and seals? Depending on what is failing/has failed inside the motor it might be a bit more complicated that that.
Are there rebuild kits available? No, apart from a kit of seals and gaskets. See attachment.
If not, where would be a good place to get a list of parts needed? The attachment is what the Parts Manual shows as being available for that motor. Anything that is not listed separately is not available without buying a complete motor. To ensure the Parts List is the correct one for your motor please check that yours has a 220-8162 Part Number tag on it.

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Thank you Nige, that info was very helpful. More than likely I will have a mechanic buddy help me. He's a diesel mechanic, but he occasionally works on construction equipment - but I don't think he's ever rebuilt one of these though.

I'm assuming only the damaged/worn parts would need to be replaced in a rebuild (along with all of the seals and gaskets) and not everything? Do you know if the seal kit listed is just the seals and gaskets listed in the list above it or are they a set of different but also necessary seals & gaskets? I'm also guessing that the most likely parts to go bad are the bearings and/or brake discs and plates (aside from a leaking seal/gasket)? Based on what I'm hearing and feeling when my machine acts up, it definitely sounds and feels like discs gradually working up against each other.

Also, I read somewhere that some systems are closed looped and do not circulate the oil from the drive motors back though the filter. Is this the case on my machine? If so, is there a way to add some sort of in-line filter within this loop to eliminate the spread of possible contaminates?

It could be a brake in the motor not releasing. If it is it should not contaminate the closed loop and should be repairable without replacing the whole motor.

Mobiltech said:

It could be a brake in the motor not releasing. If it is it should not contaminate the closed loop and should be repairable without replacing the whole motor.

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Is that something that would be intermittent? My machine operates normally for a few hours and for no apparent reason it begins to squeak and if I keep using it, within a couple minutes it turns into a grind, with noticeable resistance.

Yes it could be intermittent if the brake release piston seals are leaking the brake could come on gradually as the oil gets hotter. It is a spring applied brake so low brake pressure would make it drag.

Mobiltech said:

Yes it could be intermittent if the brake release piston seals are leaking the brake could come on gradually as the oil gets hotter. It is a spring applied brake so low brake pressure would make it drag.

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Is there a way to specifically test for that or is that done only through visual inspection?